Bracelet provided with a clasp

ABSTRACT

Bracelet provided with a foldable clasp, comprising:  
     a first arm ( 7 ),  
     at least a second arm ( 8 ) articulated with said first arm,  
     a cover ( 4, 6 ), under which the arms&#39; free extremities are folded back when the clasp is closed.  
     The cover comprises a locking system enabling the arms to be held in closed position and to be released by acting manually on said locking system to open said clasp. It further comprises a casing ( 4 ) and a base ( 6 ) closing the cover&#39;s lower side. The casing comprises solid sides of uneven thickness obtained by detach cutting machining or by molding. The casing&#39;s sides define between them and with the base an internal volume ( 45; 95 ) in which the locking system is at least partially accommodated.

[0001] This application is a continuation of application PCT/CH02/00455(WO03/022090), filed on Aug. 21, 2002, claiming priority of application2001CH-1668 of Sep. 1, 2001, the contents of which are herebyincorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention concerns a bracelet provided with a clasp,in particular a bracelet provided with a foldable clasp.

RELATED ART

[0003] Different types of foldable clasps have already been proposednotably for watch bracelets. They often comprise two or sometimes threearticulated arms that fold in closed position under a cover. One of thearms, or sometimes the cover, comprises a locking system enabling thearms to be held in folded position.

[0004] An example of such a clasp is described for example inCH-A5-668353. In this document, the cover's locking system comprises twopush-pieces provided with hooks that lock against the arms' edges inorder to hold them in closed position under the push-pieces' springload. The clasp can be opened by pressing on the push-pieces against thespring load so as to free said hooks. The locking system is entirelycontained under the cover with the exception of the push-pieces' heads,which protrude.

[0005] The clasp cover is formed of a simple plate folded on two sides.Although this process is cost-effective, it does not allow for a claspwith an attractive appearance. In particular, it is not possible toobtain a clasp with such a solid appearance and with the same surfacetreatment as the bracelet's other metallic links, which are generallyobtained by machining so as to give them an aesthetic “sculpted” andsmooth appearance. Furthermore, the cover's lower side comprises manyconcave portions in which the closing mechanism is clearly visible. Thispart is very difficult to clean and moreover risks malfunctioning whenit is exposed to transpiration and skin debris from the wearer.Furthermore, hairs and even bits of skin more often than not get pinchedunder the clasp, making the clasp uncomfortable.

[0006] A clasp showing the same inconveniences is described for examplein document EP-A1-0908112 and in document EP-A1-0914781. In the lattercase, one of the clasp's two arms is constituted by two juxtaposed arms.The closing mechanism makes use of the natural tendency of the two armsto elastically move apart from one another. The clasp can be opened bymoving the two arms towards one another by acting on two push-piecesprovided to this effect. The lock's safety however depends on theelastic force moving the arms apart, which tends to diminish with time.

[0007] In the devices described in the aforementioned documents, one ofthe bracelet's portions is fastened inside the cover, between the twofolded edges. The clasp is thus necessarily wider and thicker than thecorresponding bracelet's portion, which in most bracelets provesunaesthetic or an additional aesthetic constraint. In particular, thistype of construction does not make it possible to give a continuousappearance to the links-clasp ensemble.

[0008] It is therefore an aim of the present invention to propose abracelet provided with a foldable clasp that avoids the disadvantages ofthe prior art.

BRIEF SUMMARY OF THE INVENTION

[0009] According to the invention, these aims are achieved by means of abracelet having the characteristics of the independent claim, preferredembodiments being furthermore specified in the dependent claims.

[0010] In particular, these aims are achieved by means of a braceletclasp comprising a first arm, at least a second arm articulated with thefirst, a cover, the free extremity of the first arm being articulatedwith the bracelet said first portion, the free extremity of the secondarm being articulated with said cover, said cover being connected to thebracelet's second portion, the cover comprising a locking systemenabling the first and second arms to be held in closed position and tobe released by acting manually on the locking system to open the clasp,and wherein the cover comprises a casing and a base closing the cover.The casing comprises solid sides of uneven thickness obtained forexample by machining, by molding and/or stamping (swaging) with varyingstamping depths. The arms' width is inferior or equal to the cover'swidth, so that the arms' free extremities are folded and hidden underthe cover when the clasp is closed. The casing's sides define betweenthem and with the base an internal volume in which the locking system isat least partially accommodated.

[0011] These characteristics have notably the advantage of making itpossible to give the bracelet's clasp an external appearance very closeto that of the bracelet's other links. In particular, it is possible tomachine, mold and/or stamp the clasp so that the profile of its lateralsides is the same as the profile of said links' lateral sides. Thecasing's width and surface conditioning are furthermore preferably thesame as those of the bracelet's link rows. These characteristics, whichcannot easily be obtained from a cover formed by folding a plate havinga constant thickness, allow a bracelet-clasp ensemble to be obtainedthat has an extremely pleasing uniform and compact appearance.

[0012] Furthermore, the protecting base closing the lower side of thecover's casing enables the clasp's locking system to be effectivelyprotected and prevents it from getting jammed because of deposits ofdust or debris. The casing-base ensemble can be devoid of edges orsquare angles, making it less easily soiled and more comfortable towear. In a preferred embodiment, the base is made of a simple and cheapplate whereas the casing, which determines the cover's outer shape, hasa more solid appearance obtained by machining, by molding or bystamping. The base can possibly be done without when the cover'sthickness must be reduced, for example in the case of a leatherbracelet.

[0013] According to another advantage of the invention, it is possibleto fasten said cover directly with an ordinary link row of the bracelet.It is thus not necessary to modify the links closest to the cover; thefastening system with the cover is the same as, or is at leastcompatible with, the system used to assemble the link rows together.

DESCRIPTION OF THE DRAWINGS

[0014] Other advantages of the present invention will become apparentupon reading the description given by way of example and illustrated bythe attached drawings containing the figures, in which:

[0015]FIG. 1 shows a perspective exploded view of a bracelet claspaccording to the invention.

[0016]FIG. 2 shows a perspective exploded view from below of a firstembodiment of the clasp cover according to the invention.

[0017]FIG. 3 shows a lateral view of the locking system of the inventiveclasp.

[0018]FIG. 4 shows a perspective exploded view from below of a secondembodiment of the clasp cover according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0019]FIG. 1 shows an example of a clasp according to the invention.This clasp is designed for example to be used to close a watch braceletof the type described in patent application WO0065948. A single rowformed of two links 1, 2 of one of the bracelet's portions isrepresented in the Figure. In this example, each row is constituted of aright link 1 and of a symmetrical left link 2. The invention is howevernot restricted to bracelets comprising two links per row; it would bepossible for example to insert one or several intermediary links betweenthe marginal links 1 and 2. Similarly, the invention is not limited tothe particular illustrated shape of the links. It is furthermore alsopossible to use the inventive clasp with non-metallic bracelets, forexample with leather or rubber bracelets. The clasp itself is preferablymade of metal, but could also be of synthetic or composite material.

[0020] The links 1 and 2 of each row are held against each other betweena portion of the links of the next row. A cylindrical rod traverses allthe links of each row through an opening having a diameter slightlysuperior to that of the rod, so as to allow a rotation without play ofthe rows of links in relation to each other.

[0021] The clasp comprises a first arm 7 and a second arm 8 connected toone another in an articulated manner by means of an axis 70. The armscan be of steel or of precious metal; it is however also possible to useflexible arms, for example rubber or synthetic arms having a bendingradius adapted to the wearer's wrist. The first arm 7 comprises two armsseparated by a slit 73 in which the second arm 8 is accommodated infolded position, so that the two folded arms occupy only a singlethickness. The first arm 7 is connected in an articulated fashion arounda rod 31 with a connecting piece 3 to the bracelet's first portion andtraverses openings 71 in the horns integral with the first arm 7. Theshape of the connecting piece 3 enables the two links 1, 2 of the firstrow to be held together and to articulate them around a rod 32. The rod31 is preferably visible and accessible from the flanks of theconnecting piece 3; it is thus possible to drive it out by means of anappropriate tool to remove the links 1 and 2 and thus modify thebracelet's length. In a variant embodiment, it is also possible to forgothe intermediary piece 3 and to connect the first links 1, 2 directlywith the first arm 7 whose shape will be adapted accordingly.

[0022] The second arm 8 is connected with the clasp's cover 4, 6 aroundan axis 81 traversing the openings 41. The cover comprises a casing 4and a base 6 removably fastened to one another. According to theinvention, the openings 41 are located in a plane between the plane ofthe base 6 and the upper side of the base; in this manner, theconnection between the casing 4 and the second arm 8 does not increasethe cover's overall thickness. Furthermore, the risk of the skin orhairs being pinched at the articulation is minimized. The openings 41are furthermore provided on the cover's side opposite the bracelet'ssecond portion (on the left in the Figure) so as to increase the lengthof the second arm 8 and the bracelet's outspread range. When the claspis opened, this construction furthermore allows the cover 4, 6 to beheld naturally in a plane between the plane of the second arm 8 and theplane of the bracelet's second portion, thus facilitating the handlingof the cover that will not risk swinging in a vertical positionperpendicular to the bracelet.

[0023] A scalloping in the cover 4 enables a row of two links of thebracelet's second portion (not represented) to be fastened theredirectly. The shape of the scalloping corresponds to the shape of thescalloping formed between two juxtaposed metallic links of each row ofthe bracelet; it is thus possible to fasten any ordinary links directlyto the cover. The links are connected in an articulated fashion by meansof a rod 42 and held between the casing's two parallel sides 47. The rod42 can preferably also be removed to take off or add rows of links inorder to modify the bracelet's length. All the axes enabling the coverto be fastened to the clasp and to the bracelet traverse openings 41, 42through the solid casing 4, thus avoiding stress on the less rigid base6.

[0024] The base 6 makes it possible to close the lower side of the cover4 whilst leaving an empty volume 45 for accommodating the locking system5. This locking system enables the casing of the cover 4 to be held infolded position over the first portion 7. The base 6 is provided withtwo slits 60 traversed by hooks 500 510 (visible in FIG. 3) acting asholding means to hook themselves in closed position with the first arm 7by traversing the openings 72 provided to this effect. The hooks areguided between the holding position and the released position by theedges of the slits 60. The clasp can be opened by pressingsimultaneously on the two push-pieces 54, 55 protruding on each side ofthe cover 4 through the lateral openings 40, so as to move the hookscloser to one another to disengage them from the openings 72. It isimpossible to open the clasp by acting on a single push-piece. The hooks500, 510 are directly connected to the buttons 54, 55; the user thusdirectly senses the range of the movement effected by the hooks, whichallows him to perfectly feel the button's action and the moment when theunhooking is accomplished. The openings 40 traversing the lateral sides46, 48 of the housing 4 enable the locking system 5 to be held even whenthe base 6 is unscrewed, thus making easier the cover's disassembly, forexample for cleaning.

[0025] The openings 72 make it possible to fasten the cover's hooks 500,510 on each side of the second arm 8 rather than in its extension. Thesefastening means thus do not restrict the maximal length of the secondarm, which is nearly as long as the first arm 7. This characteristicallows the outspread range of a clasp of given length to be maximized.

[0026] A first embodiment of the cover is represented in FIGS. 2 and 3.In this example, the cover is constituted by a casing 4 and a base 6screwed onto this casing by means of two screws through holes 61 engagedin threads 43 and preferably stopped by a point of glue. The screws arevisible only on the cover's lower side. When the clasp is folded, i.e.when the bracelet is worn, its external appearance is determinedexclusively by the casing 4 whereas the base 6 and the screws are hiddenbetween the casing 4 and the arms 7, 8. The casing's external appearanceis thus better crafted than that of the base 6. In this example, thecasing 4 has a solid appearance and is preferably manufactured by detachcutting machining, by molding and/or stamping with varying stampingdepths, i.e. preferably with the same method as that used formanufacturing the bracelet's links 1, 2. Stamping with varying stampingdepths means here a stamping method with a stamp or die comprising anon-plane resting surface with the piece to stamp.

[0027] It is thus possible to make a casing comprising solid sides 44,46, 48 of uneven thickness and whose profile of its lateral sides ispreferably the same as the profile 19 of the lateral sides of thebracelets' links 1, 2.

[0028] The same surface conditioning will also preferably be applied tothe casing 4 as to the links 1, 2. Finally, in a preferred embodiment,the width of the casing is equal to that of the bracelet's link rows.The width of the arms 7 and 8 is preferably less than that of the coverand links, so that they are hidden under the bracelet and the cover. Itis thus possible to obtain a homogenous bracelet-clasp ensemble that isvery aesthetic and comfortable, which could not be realized if thecasing were manufactured by plate folding or by a manufacturing processdifferent from that used for the links.

[0029] The base 6, which is more often than not hidden, can bemanufactured with a cheaper method, in this example by folding andstamping of a plate having an even thickness. It is accommodated in ashoulder 430 in the casing 4 so as to avoid any edges that mighthurt/injure or irritate the wearer of the watch. The casing-baseensemble is thus practically devoid of any projection and presents acompact external appearance. The external side of the base 6 is planeand rests with its whole length against the arms 7, 8 of the foldedclasp, so that no dirt deposits can accumulate under the cover. Theupper side of the casing 4 is however preferably arched in the directionof the bracelet's curve. The cover 4, 6 is devoid of any abrupt anglesor concave portions, making it less easily soiled. Finally, the base 6enables the locking system 5 to be effectively protected against dust ordebris and prevents it from getting jammed.

[0030] The base 6 is provided in this example with a tongue/tab 62preventing the base from becoming disunited from the casing 4 when theclasp is in closed position, even if the screws in the holes 61 shouldaccidentally become totally unscrewed.

[0031]FIG. 3 shows the detail of the locking system 5 of the cover inclosed position. It comprises in this example two push-pieces 54, 55provided each with two recesses 51, 50. The two extremities of twoextensible rods 52, 53 are lodged in the two recesses 51, 50 of the twopush-pieces. The extensible rods 52, 53 are in this example constitutedby a middle metallic rod and by an elastic spring 520, 521 lodged at thebottom of each recess, on both extremities of the rods. It would howeveralso be possible, in a variant embodiment, to put only a single springat one of the two extremities of the two rods 52, 53 or, in anothervariant embodiment (not illustrated) to use bars constituted of twohollow half-rods inside of which an elastic spring is lodged that tendsto move these rods apart.

[0032] The use of two parallel rods 52, 53 ensures that the push-pieces51, 52 move without swiveling when they are actuated. In a variantembodiment that is more economical or adapted to smaller clasps, itwould however be possible to use a single rod instead of two, forexample an extensible rod of non cylindrical shape. It is also possible,though not recommended, to use a single push-piece acting on a singlehook rather than a locking system having two push-pieces.

[0033]FIG. 4 illustrates a variant embodiment of the cover according tothe invention. In this embodiment, the base 10 is fastened to thecover's casing 9 by means of the rods 91 respectively 92 enabling thecover 9, 10 to be assembled with the clasp's second arm 8, respectivelywith the bracelet's second portion. The rod 91 traverses an extremity ofthe casing, the holes 102 in the base and the opening 81 in the secondarm 8. The other rod 92 traverses the casing's other extremity, theholes 101 in the base and the two links (not represented) of the firstrow of the second portion. This variant embodiment thus does not use anyscrews, which are always at risk of becoming unscrewed. On the otherhand, the base 10 cannot be made from a simple plate but must bemanufactured by detach cutting machining, molding or stamping with anon-plane stamp or die, which renders it more expensive. Furthermore,the machining tolerance must be accurate in order to prevent the basefrom lifting off and allowing the locking system 5 to come out when therod 91 is removed in order to modify the bracelet's length.

[0034] In this variant embodiment, the casing 9 also determines theaesthetic appearance of the closed clasp. It thus also presents sides94, 96, 98 of uneven thickness according to the desired design.

[0035] It will be understood that the inventive bracelet ischaracterized first and foremost by the particular structure of theclasp's cover. This cover can however also be used with clasps of othertypes, notably clasps having three arms of the wallet or butterfly type,or clasps allowing the length to be adjusted.

1. Bracelet provided with a foldable clasp, comprising: a first arm, atleast a second arm articulated with said first arm, a cover, the freeextremity of the first arm being articulated with a first portion of thebracelet, the free extremity of the second arm being articulated withsaid cover, said cover being connected to the bracelet's second portion,said cover comprising a locking system enabling the first and secondarms to be held in closed position and to be released by acting manuallyon said locking system to open said clasp, said cover comprising acasing and a base closing said cover, said sides of the casing definingbetween them and with the base an internal volume in which said lockingsystem is at least partially accommodated, characterized in that saidcasing comprises solid sides of uneven thickness, and in that the freeextremities of said arms are folded back under said cover when the claspis closed.
 2. Bracelet according to claim 1, wherein said locking systemcomprises: at least one holding means for holding said arms against oneanother in folded position when said holding means is in closedposition, at least one elastic means for forcing the holding means intoclosed position, at least one push-piece for acting against the force ofthe elastic means and release the holding means by pressing on thepush-piece.
 3. Bracelet according to claim 2, wherein said base furthercomprises at least one opening, said holding means being guided by theedges of said opening between the closed position and the releasedposition of the clasp.
 4. Bracelet according to claim 2, comprising twopush-pieces, said holding means being released only when said twopush-pieces are actuated separately.
 5. Bracelet according to claim 2,wherein said elastic means comprise at least one extensible rod, each ofwhose two extremities are lodged in a recess in two distinctpush-pieces, said at least one holding means comprising two hooks, eachbeing integral to one of said push-pieces and hooking in said closedposition at least one of said arms.
 6. Bracelet according to claim 5,said elastic means comprising two rods parallel to one another. 7.Bracelet according to claim 1, wherein said locking system works withthe hooking means disposed on the first arm on each side of the secondarm so as to avoid limiting the maximal length of the second arm. 8.Bracelet according to claim 1, said base being removably fastened tosaid casing.
 9. Bracelet according to claim 8, said base comprising atongue preventing the base from becoming disunited from said casing whensaid clasp is in closed position, even if said base is unscrewed. 10.Bracelet according to claim 8, said base being screwed onto said casingby means of screws visible only on the lower side of said cover. 11.Bracelet according to claim 1, said base being formed from a plate ofeven thickness.
 12. Bracelet according to claim 1, said base beingfastened to said casing by means of the rods enabling the cover to beassembled with the clasp's second arm, respectively with the bracelet'ssecond portion.
 13. Bracelet according to claim 1, said portions eachcomprising several links, the profile of said casing's lateral sidesbeing the same as the profile of the lateral sides of said links. 14.Bracelet according to claim 13, said portions each comprising severalrows of links, the width and surface conditioning of said clasp beingthe same as those of said bracelet's rows of links.